1. Field of the Invention
This invention relates to an outboard motor provided with a cowling for accommodating an engine and an air duct for introducing ambient air into the cowling.
2. Description of the Related Art
Outboard motors typically are mounted at the stern of the boat. This positioning subjects the outboard motor to water splashes and the like during operation of the boat. Simultaneously, a cowling of an outboard motor must allow air to flow into the cowling to provide intake air for the engine. Accordingly most outboard motor cowlings have a water separation structure that separates water from the air inducted into the cowling and supplies the air to the engine.
For instance, Japanese Patent Publication No. 11-034984 teaches an outboard motor in which the space inside the cowling is divided into an air inlet chamber located above the engine and an engine accommodating chamber. An air duct is provided for guiding the air inducted into the air inlet chamber toward the engine accommodating chamber. In this structure, a swirling air flow circling around the outer face of the air duct is generated in the air inducted from the air inlet openings, thus separating water from the air.
During reverse operation, or at hard acceleration or deceleration, rising waves often splash onto such outboard motors. Water from such waves can sometimes enter the cowling and make its way into the engine accommodating chamber by way of the air duct.